What is metamask-mobile AGENTS.md?

A set of coding instructions for the MetaMask mobile project. It covers the project overview, important commands, setup, installation, and Expo development.

It helps with MetaMask mobile setup, JavaScript-only development, Expo development, and following the project's essential commands.

It gives an agent the project-specific context and procedures needed to work consistently in the repository.

How MetaMask/metamask-mobile configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to MetaMask/metamask-mobile. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/MetaMask/metamask-mobile/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/MetaMask/metamask-mobile

Made for: Codex, OpenCode.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/metamask/metamask-mobile/agents-md/github.svg)](https://agentmods.dev/instructions/metamask/metamask-mobile/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/metamask/metamask-mobile/agents-md"><img src="https://agentmods.dev/badge/instructions/metamask/metamask-mobile/agents-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/metamask/metamask-mobile/agents-md"><img src="https://agentmods.dev/badge/instructions/metamask/metamask-mobile/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 2,559 This file is loaded in full into every session.

When invoked 2,559 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin unknown No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.02559	$0.02559
Opus 5.5	$0.01024	$0.01024
Sonnet 5.5	$0.00512	$0.00512
Haiku 4.5	$0.00256	$0.00256

Measured 3d ago against content hash 094f4c6e9edb, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

metamask-mobile AGENTS.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

AGENTS.md · 253 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

3d ago Changed · -2 lines · -21 tokens per session 094f4c6e9edb
14d ago Changed e71c9188f0e5
18d ago Changed · +2 lines · +21 tokens per session 4265b30225ef
28d ago Changed · +2 lines · +144 tokens per session 8f2c4320cdbf
1mo ago Changed · +23 tokens per session 87e2e48a50a4
2mo ago Changed e2a47904350e
2mo ago First seen · 251 lines · 2,392 tokens per session scan A 7f52b0db8fa8

Subscribe to this mod's changes

metamask-mobile AGENTS.md is an instructions file published in the GitHub repository MetaMask/metamask-mobile (3,082 stars, last pushed yesterday), with no licence file. It adds 2,559 tokens to every session, about $0.0102 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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metamask-mobile AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
metamask-mobile AGENTS.mdMetaMask/metamask-mobile	Instructions file	3.1k	yesterday	none	A	2,559	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	yesterday	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

metamask-mobile: Instructions file for Codex